Laser glass host compositions comprising teo{11 , bao and pbo

ABSTRACT

Laser glass host compositions for effective lasing amounts of Nd2O3 are disclosed, the host compositions comprising TeO2, BaO and PbO in certain molar proportions. Also disclosed are methods of making highly effective laser articles, such as rods and discs, and the new use of the above-described TeO2/BaO/-PbO glass compositions for forming laser articles, the new use including forming a laser article from the compositions; pumping the laser article to provide an energy inversion; and lasing the pumped article.

United States Patent [191 Cooley 51 Oct. 29, 1974 LASER GLASS HOST COMPOSITIONS COMPRISING TEO BAO AND PBO [75] lnventor: Richard F. Cooley, Toledo, Ohio [73] Assignee: Owens-Illinois, lnc., Toledo, Ohio [22] Filed: June 27, 1973 [21] Appl. No.: 373,923

[52] U.S. Cl ..331/94.5 E, 252/301.4 R, 5 1 F 195/419 [51] IfiffClIQlQQ/HOTS 3/00,C03c 3/12, C03c 3/30 [58] Field of Search 106/47 Q, 47 R; 331/94.5 E; 252/3014 R, 301.4 F; 301.6 R

[56] References Cited UNITED STATES PATENTS 3,423,326 1/1969 Redman 252/3016 R FOREIGN PATENTS OR APPLICATIONS 736,073 8/1955 Great Britain 106/47 Q 741,986 12/1955 Great Britain... 106/47 Q 1,496,561 9/1972 Germany 106/47 O OTHER PUBLlCATlONS Stanworth, Tellurite Glasses, J. Soc. Glass Tech., vol. 36, (1952), pp. 217-241, TP845 S 678.

Primary ExaminerWinston A. Douglas Assistant ExaminerMark Bell Attorney, Agent, or FirmRichard D. l-leberling; E. J. Holler [5 7 ABSTRACT 6 Claims, 1 Drawing Figure PAIENTEU um 29 I974 @Qq A LASER GLASS HOST COMPOSITIONS COMPRISING TEOg, BAO AND PBO INVENTION The present invention relates to glass host compositions for effective lasing amounts of Nd O the host compositions comprising TeO BaO and PhD in certain molar amounts. The present invention also relates to methods of making highly efficient laser articles from the above-described glass compositions. The present invention also relates to the new use of a TeO BaO/PbO glass composition for making glass laser articles, the new use including making the laser articles from the compositions, pumping the articles, and lasing the pumped articles.

It is desirable to provide improved laser glass compositions that can be used to make highly efficient glass laser articles, such as rods and discs. It is also desirable to provide methods of making the articles and also to provide the new use for TeO /BaO/PbO glass compositions for making glass laser articles, the new use including forming a glass laser article from the compositon, pumping the laser article, and lasing the pumped article.

it is an object of the present invention to provide a laser glass composition comprising TeO2, B210 and P56 in which the proportions of TeO BaO and PhD in molar amounts are defined in a general range by the area within the heavy lines connecting the points ABC- DEF of the ternary diagram of the FIGURE of the drawings, the glass composition being a host for an effective lasing amount of Ndgog.

It is an object of the present invention to provide a method for making a glass article in which the method comprises the steps of:

l. melting laser glass batch-forming materials to provide a molten glass comprising TeO BaO and PhD in which the molar proportions thereof are defined by the area within the heavy lines connecting the points ABC- DEF of the ternary diagram of the FIGURE, the molten glass being a host for an effective lasing amount of Ndgog;

2. forming a glass laser blank from the molten glass; and

3. fabricating a laser article from the blank to provide an efficient laser article.

it is an object of the present invention to provide the new use for a glass composition for a glass article in which the glass comprises TeO BaO and PbO in certain molar proportions and in which the glass composition is a host for an effective lasing amount of Nd O the new use comprising the steps of:

l. forming a glass laser article from the glass composition comprising TeO BaO and PhD, along with the effective lasing amount of Nd- O 2. pumping the laser article to provide an energy inversion; and 3. lasing the pumped article.

it is an object of the present invention to provide an efficient glass laser article made from a glass composition comprising TeO BaO and PhD, and containing an effective lasing amount of Nd O These and other objects will be apparent from the specification that follows, the appended claims, and the drawings, in which the FIGURE is a ternary diagram of the glass host composition of the present invention in which the molar proportions of TeO- B210 and PhD are defined by the areas within the heavy lines of the ternary diagram.

The present invention provides outstanding laser glass host compositions for effective lasing amounts of Nd O the host compositions comprising TeO BaO and PbO in certain molar proportions thereof that are defined in a general range by the area within the heavy lines connecting the points ABCDEF of the ternary diagram of the FlGURE of the drawings.

Preferably, the molar porportions of TeO BaO and PbO are defined by the area within the heavy lines connecting the points GHIJ KL of the ternary diagram. The optimum glass host compositions contain molar amounts of TeO B210 and PhD that are defined in an optimum range by the area within the heavy lines connecting the points MNOP in the ternary diagram.

The present invention also provides methods for making highly efficient glass laser articles, the methods including the steps of:

l. melting laser glass batch-forming materials to provide a molten glass comprising TeO BaO and PhD in which the molar proportions thereof are defined in a general range by the area within the heavy lines connecting the points ABCDEF of the ternary diagram, the molten glass capable of acting as a host for an effective lasing amount of Nd O 2. forming a glass laser blank from the molten glass; and

3. fabricating the outstanding laser articles from the glass laser blank.

The present invention also provides the new use for a glass composition as a glass laser article in which the glass comprises TeO BaO and PbO in certain molar proportions that are defined in a general range within the area formed by the heavy lines connecting the points ABCDEF of the ternary diagram, and in which the glass composition is a host for an effective lasing amount of Nd O the new use comprising the steps of:

l. forming a glass laser article from the glass composition comprising TeO BaO and PbO;

2. pumping the laser article to provide an energy inversion; and

.3. passing monochromatic light through the article to provide a stimulated emission at a wavelength of about 1.06 microns.

A zinc tellurite glass consisting essentially of a major molar proportion of Te0 and between about 20 and 40 molar percent of ZnO is described and claimed in the Redman U.S. Pat. No. 3,423,326. These zinc tellurite glasses were reported as having some fluorescent activity when doped with M1 0 As previously indicated, the outstanding laser glass host compositions of the present invention unexpectedly exhibit much higher fluorescent activity than the zinc tellurite glasses of U.S. Pat. No. 3,423,326, the increased fluorescent activity indicating a greater laser efficiency for laser articles made from the host compositions of the present invention.

As previously described, only certain molar proportions of TeO BaO and PbO can be used to provide the highly efficient laser articles, such as rods and discs. The increase in fluorescent activity of the glasses of the present invention, when compared to the working examples of U.S. Pat. No. 3,423,326, is generally at least about 50 percent and preferably at least about 60 or EXAMPLE 1 PART A A gram melt was prepared by mixing reagent grade raw materials, in the following molar percent and also for convenience, weight percent, with ml. of

water.

Ingredients Mole Percent Weight Percent Host Glass Laser Article Host Glass Laser Article ticles can be made from a laser glass compositioifiion taining only certain molar proportions of TeO B210 and PbO. 20

In general, the glass host composition of the present invention contains about 70-86 mole percent TeO- about 2-25 mole percent BaO, and about 0.2-18 mole percent PbO.

Preferably, the laser glass host compositions comprise about 73-82 mole percent TeO about 4-22 mole percent B110, and about 0.2-1? mole percent PbO.

The most preferred host glass compositions contain about 75-80 mole percent TeO about 5-20 mole percent BaO, and about 0.2-15 mole percent PbO. The 3 host compositions of the present invention contain generally about 001-1 .5 mole percent Nd O and preferably about 0.3-1.0, and optimally about 0.4-0.9 mole percent Nd O Good results have been obtained when the laser glass host composition comprises about 75 mole percent TeO- about 20 mole percent BaO, and about 5 mole percent PbO or about 75 mole percent TeO about 10 mole percent BaO, and about 15 mole percent PbO.

ln accordance with the present invention, the increase in fluorescent activity for laser articles for the present invention is surprisingly at least about 50 percent over that of a zinc tellurite glass containing about 65 mole percent Te0 and 35 mole percent ZnO.

The increase in fluorescent activity is at least about percent greater than that of a lithia-calcia-alumino silicate glass laser composition as set forth in U.S. Pat. No. 3,471,409 to Lee and Rapp, the laser composition comprising the following ingredients in approximate mole percentages: 50

Mole Percent 7W l ngrcdient SiO 6( 5 Al- O, 0 27.5 C110 10 Nd 0.5

""TEQMFrWAEfiTiXEd' for and poured into a gold crucible. The crucible was placed in an air circulating oven with the temperature maintained at l 10C. overnight to remove the water. The crucible was then placed in an electric resistance furnace with the temperature at 750C. for 3 hours, or until homogenous, after which the molten glass immediately poured into 5 a preheated (260C.) graphite mold forming a disc having an 1 l/ 16 inch diameter and 1/4 inch thickness. The graphite mold was placed in an annealing oven maintained at 340C. After 1 hour, at 340C., the temperature of the annealing oven was lowered at a rate of 0 38C. per hour to 250C. after which the annealing oven was turned off and the mold cooled to room temperature.

The solid, annealed glass disc was removed from the mold, wet ground and polished with close tolerance to a thickness of 0.195 inches and a diameter of 0.687 inches. The refractive index of the finished polished glass disc was measured to be 2.19.

PART B The polished glass disc from Part A was tested for fluorescence intensity and decay time in a high power pulsed test system. The disc was placed in a holder and exposed to a beam of light from an E6 & G model FX 12-25 xenon flash lamp. The flash lamp had a flash duration of about 20 microseconds. The disc was not observed to solarize after repeated excitation by the flash lamp. The fluorescence intensity and decay time of the excited sample was measured by photographing the oscilloscope display of the 1060 nanometer fluorescent intensity versus time on a Tektronix Model 556, Dual Trace oscilloscope connected to an RCA S-l photomultiplier, having a narrow band pass filter.

The fluorescence intensity measurement was normalized against ED-2, a glass laser composition of Owenslllinois, lnc., comprising, in mole percent, 60.0% SiO 2.5% A1 0 27.5% Li O, 10% CaO, 0.16% Ce0 and 0.5% Nd O disclosed in U.S. Pat. No. 3,471,409, as Example 1. The fluorescence intensity was found to be 3.49 when normalized against the glass laser composition; 3.49 times the intensity of the glass lasercomposition.

The fluorescence intensity was corrected for the refractive indices of the glass disc and the reference glass laser compositionb disc) n 7 6v The corrected fluorescence intensity was 1.72. The flu-. The efractive index Ofthe finished polished glass disc orescence decay time was 140 microseconds. A w was measured to be 2.18.

EXAMPLE 2 PART B PART 5 The polished glass disc from Part A was tested for fluorescence intensity and decay time as described in Part A gram melt was Prepared and Pollshed glass discs B of Example 1. The normalized fluorescence intensity Prepared therefrom as desirlbed in Part A of Example was 3.51 and the corrected fluorescence intensity was 1, except the molar or welght Percentages of the raw 1.77. The fluorescence decay time was 140 microsece -"P we e tq letei V r, ,7 10 onds. m

Ingredients Mole Percent Weight Percent Host Glass Laser Article Host Glass Laser Article TeO, 80.0 79.5 78.9 77.7 3210 15.0 14.8 14.2 13.9 PbO 5.0 4.9 6.9 6.7 Ndgog 0.8 1.7

The refractive index of the finished polished glass disc Other specific glass laser compositions set forth was measured to be 2.12. herein as being suitable for use in the present invention can be substituted for the specific glass laser composi- PART B tions used in the working examples to provide substan- The polished glass disc from Part A was tested for flutially equivalent results. For instance, any of the comorescence intensity and decay time as described in Part positions set forth within the area formed by the heavy B of Example 1. The normalized fluorescence intensity lines connecting the points ABCDEF of the ternary dia .was 3.7 and the corrected fluorescence intensity was gram can be used in place of any of the specific laser 1.95. The fluorescence decay time was 145 microseccompositions used in the working examples. As previ- Onds ously indicated, any of the glass laser compositions set forth within the area formed by the heavy lines con- EXAMPLE 3 necting the points Gl-lIJ KL of the ternary diagram can PART A be used to provide an increased laser efficiency of at least percent over a zinc tellurite glass containing only tellurium oxide and zinc oxide, as described in the Redman patent or at least 50 percent of the previouslydescribed lithia;calcia-alumino silicate laser glass. ln

A 15 gram melt was prepared and polished glass discs prepared therefrom as described in Part A of Example 1, except the molar or weight percentages of the raw materials were as follows:

Ingredients Mole Percent Weight Percent Host Glass Laser Article Host Glass Laser Article 8110 20.0 19.8 18.9 18.6 PbO 5.0 4.9 6.9 6.7 Nd o 0.8 1.7

The refractive index of the finished polished glass disc most cases, the increase fi l y i f wa r d t b 2,09, 45 least to percent when the composmon 1s wlthm the area formed by the heavy lines connecting the PART B points GHlJ KL, or the optimal range of the area The polished glass disc from Part A was tested for fluformed by the heavy lines connecting the points orescence intensity and decay time as described in Part MNQP- The Increase in fluorescent 1ntens1ty and lasing B of Example 1. The normalized fluorescence intensity 5 effic1ency is often as high as about percent or more was 4.4 and the corrected fluorescence intensity was h n compare to the Working examples of the Red- 2.39. The fluorescence decay time was 132 microsecjmgaten W V H 7 w,

onds. V V W i EXAMPLE 4 What is claimed is:

PART A 55 l. A laser glass composition comprising:

' 1. a host glass contammg about 70-86 mole percent A 15 gram melt was P P 'F n Polished glass discs TeO about 2-25 mole percent BaO, and about prepared therefrom as descnbed 1n Part A of Example 2 3 l percent p o; and 1, except the molar or weight percentages of the raw 2, a ff ti l si amount f Nd materials e as w ileaisla s mp itiqn.s mn s e Ingredients Mole Percent Weight Percent Host Glass Laser Article Host Glass Laser Article TeO, 80.0 79.5 75.7 74.6 BaO 5.0 4.9 4.5 4.4 Pbo 15.0 14.8 19.21 19.5 1 -1d,o 0.11 1.5

l. a host glass containing about 73-82 mole percent TeO about 4-22 mole percent BaO, and about 0.2-1? mole percent PhD; and

2. an effective lasing amount of Nd O 3. A laser glass composition comprising;

1. about 75-80 mole percent TeO about 5-20 mole percent BaO, and about 02-15 mole percent PhD; and Y 2. an effective lasing amount of Nd- O 4. A laser glass composition as defined in claim 1 in which the host glass comprises about 75 mole percent TeO about 20 mole percent BaO, and about 5 mole percent PhD.

5. A laser glass composition as defined in claim 1 in which the glass host comprises about 75 mole percent TeO about mole percent 8210, and about mole percent PbO.

6. The new use for a glass composition as a glass laser article in which the proportions of TeO B210 and PbO in molar amounts are defined by the area within the heavy lines connecting the points ABCDEF in the ternary diagram in the FIGURE of the drawings, and in which the glass composition is a host for an effective lasing amount of Nd O the new use comprising the steps of:

l. forming a laser article from the glass laser composition;

2. pumping the laser article to cause an energy inversion; and

3. passing monochromatic light through the article to cause stimulated emission at a wave length of about 1.06 microns. 

1. A LASER GLASS COMPOSITION COMPRISING:
 1. A HOST GLASS CONTAINING ABOUT 70-86 MOLE PERCENT TEO2, ABOUT 2-25 MOLE PERCENT BAO, AND ABOUT 0.2-18 MOLE PERCENT PBO, AND
 2. AN EFFECTIVE LASING AMOUNT OF ND2O3.
 2. an effective lasing amount of Nd2O3.
 2. A laser glass composition comprising:
 2. an effective lasing amount of Nd2O3.
 2. an effective lasing amount of Nd2O3.
 2. pumping the laser article to cause an energy inversion; and
 3. passing monochromatic light through the article to cause stimulated emission at a wave length of about 1.06 microns.
 3. A laser glass composition comprising:
 4. A laser glass composition as defined in claim 1 in which the host glass comprises about 75 mole percent TeO2, about 20 mole percent BaO, anD about 5 mole percent PbO.
 5. A laser glass composition as defined in claim 1 in which the glass host comprises about 75 mole percent TeO2, about 10 mole percent BaO, and about 15 mole percent PbO.
 6. The new use for a glass composition as a glass laser article in which the proportions of TeO2, BaO and PbO in molar amounts are defined by the area within the heavy lines connecting the points ABCDEF in the ternary diagram in the FIGURE of the drawings, and in which the glass composition is a host for an effective lasing amount of Nd2O3, the new use comprising the steps of: 